Felder



No. 625,842. Patented A. W. ODPYlNG DEVlGF. FOR DOCUMENTS, DRMMNGS; 81.0. cation med Nov. 2

(App 6, 1598.)

(No I lodeL) THi NORRIS PETERS co.. PHOTO-UTHO WASHWGTON, n. c.

May 30, \899.

. shown in the drawings.

UNITED STATES I PATEN'L OFFICE.

ALEXANDER IIIN, BERLIN, GERMANY, ASSIGNOR TO LUDWIG WVAITZ- FELDER, OF HAMBURG, GERMANY.

COPYING DEVICE FOR DOCUMENTS, DRAWINGS, 84C.

SPECIFICATION forming part of Letters Patent No. 625,842,dated May 30, 1899.

Application filed November 25, 1898. Serial No. 697,433. (No model.)

To all whom it may concern.-

Be it known that I, ALEXANDER IHN, a subject of the King of Prussia, German Emperor, and a resident of Berlin, in the Kingdom of Prussia, German Empire, have invented certain new and useful Improvements in Copying Devices for Documents, Drawings, and the Like, of which the following is an exact specification.

This invention relates to an improved copyin g device or apparatus for documents, drawings, and the like, the novelty of the said device consisting in the combination of the features hereinafter described.

In my apparatus I use a strip of fabric or stud prepared in an especial manner. The copying mass is placed over the strip of fabric, which latter afterward is stretched over a zinc plate.

In order to make my invention more clear, I refer to the accompanying drawings, in which- Figure 1 shows aplan View; Fig. 2, a vertical section of the same.

Proceeding to describe the drawings, I remark that the apparatus consists in general of the already-mentioned strip of fabric or stuff ct, which is impregnated with a solution of the formula following hereinafter: fifty grams Halle acid, consisting of ninety per cent. alcohol and ten per cent. sulfuric acid,

one hundred. grams acetic acid of eighty-six per cent, and one hundred and fifty grams distilled water. This impregnation of the fabric forms a characteristic feature of my invention, making it absorb the ink very quickly. Further, it must be stated that the ink will disappear after a certain time, so that a new original can be pressed upon the fabric. After this impregnation the strip of fabric or stuff a is stretched over a zinc plate 1). (Shown in the sectional view Fig. 2.) A cardboard plate 0 is then preferably placed behind the zinc plate I), and the hereinbefore-described parts then arranged within or encompassed by a casing (1, said casing cl allowing the front of the apparatus to be exposed in the manner The impregnation of the said strip of fabric or stud Ct with the above-mentioned sulfuric acid (diluted by alcohol) and acetic acid has the efiect that p when the copying-ink is brought upon the copying mass e for the purpose of producing the desired original and subsequent copies the said copying-ink, in consequence of the influence of these acids, is caused to become absorbed into the said strip of fabric in a comparatively very short space of time, this rapid absorption of the copying-ink being an especial feature of my improved copying apparatus.

In hitherto-known hectographic and similar absorption copying devices the said absorption of the ink into the composition occupied even up to thirty-six hours, while in my improved apparatus such absorption takes place in or occupies only aboutisix hours. Furthermore, in my improved apparatus thirty originals and from each original about one hundred copies can be taken without the necessity of washing the copying mass, while in the known copying devices (employing hectographic absorption mass) such devices have often been found to become unserviceable when only four originals have been copied upon the copying mass.

My special copying mass consists of two parts gelatin dissolved'in three parts of water, whereafter three parts of glycerin (twentyeight per cent.) without lime and acid are added.

In order to make copies by means of my improved apparatus, I merely stretch the im- I am aware that similar devices are known the impregnation of the said fabric strip with the acid mixture, (or composition hereinbefore mentioned,) and, secondly, by the employment of a zinc plate upon which the said strip is stretched. The employment of a zinc plate also has the advantage that, as is clear, the copying mass cannot be injured by spots of rust which would be present in the mass if the mass were placed upon fabric stretched over a sheet-iron plate, which would cause the formation of rust, while in using a Zinc plate this would be impossible. As a further advantage I may mention that the employment of the zinc plate, as well as the cardboard plate behind the same, imparts to the copying mass a much firmer consistency than when the same is merely inclosed within a metal casing.

Having thus fully described the nature of (diluted by alcohol), and acetic acid, the said strip of fabric being stretched across the said zinc plate; a copying mass 6 spread over the fabric 1) and a frame or casing (1 arranged to partly surround the beforesaid parts, as set forth.

In witness whereof I have hereunto set my hand in presence of two witnesses.

ALEXANDER II-IN.

Witnesses:

E. L. GOLDSOHMIDT, FRITZ SPERLING. 

